/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.lvyh.lightframe.sharding.client.util;

import org.apache.commons.lang3.StringUtils;

import java.util.Optional;
import java.util.stream.Stream;

/**
 * @author lvyh 2021/10/29.
 */
public class CommonUtils {
    public static void main(String[] args) {
        System.out.println(CommonUtils.convertColumn("update_time"));
    }

    public static String convertColumn(String source) {
        if (StringUtils.isNotBlank(source)) {
            if (source.contains("_")) {
                Optional<String> reduced = Stream.of(source.split("_")).reduce((s1, s2) -> s1 + firstUpperCase(s2));
                if (reduced.isPresent()) {
                    return reduced.get();
                } else {
                    return "";
                }
            } else {
                return firstUpperCase(source);
            }
        } else {
            return "";
        }
    }

    /**
     * Capital conversion
     *
     * @param field
     * @return
     */
    public static String firstUpperCase(String field) {
        if (StringUtils.isNotBlank(field)) {
            char[] cs = field.toCharArray();
            cs[0] -= 32;
            return String.valueOf(cs);
        } else {
            return field;
        }
    }

    /**
     * Initial lowercase conversion
     *
     * @param field
     * @return
     */
    public static String firstLowerCase(String field) {
        if (StringUtils.isNotBlank(field)) {
            char[] cs = field.toCharArray();
            cs[0] += 32;
            return String.valueOf(cs);
        } else {
            return field;
        }
    }

}
